Radiant floor heating panel



M n -tr June 22 1954 RAPP 2,681,796

RADIANT FLOOR HEATING PANEL Filed Jan. 5, 1951 g Q I [Hr/E 171. 7.2

Geoz gefl B02010 Patented June 22, 1954 UNITE D STATES PATENT OFFICERADIANT FLOOR HEATING PANEL George M. Rapp, Hamden, Conn., assignor to.Houdaille Hershey Corporation, Detroit, Mich.,

a corporation of .Michigan Application January 5, 1951, Serial No.204,605

1 Claim.

This inventionrelates to a radiant floor heating panel and moreparticularly to a radiant fioor heating panel in the form of a plate andtubetype heat exchanger incorporated in a floor structure to-define asub-floor surface.

Radiant floor heating for residential and similar structures has'beenproposed in the prior art. Such heating is provided by iluidconduitsembedded in a concrete or similar floor structure. Generally, sinuousmetallic or ceramic conduits are utilized for the conveying of a heatexchange fluid, usually Water or air, in heat transfer relation with thefloor.

These prior art structures have been disadvantageous in thatextensivesite-labor is necessary to "custom fit each installation to thestructure, resulting in relatively-high installation cost. Further, aslow heating response is obtained due to the actual embedding of theconduits within the floor structure with the resultant'heating timelagcausing poor control of interiortemperatures In addition to thesedisadvantages, the finished radiant'floor heating structure typicallyprovides a relatively uneven surface whichrequires special leveling inpreparation for the application of conventional floor coverings, such aslinoleum, asphalt, tile, or thelike.

The present invention provides an improved radiant floor heating panelwhich utilizes plate and tube-type heat exchangers with the backingplates of the exchangers being superimposed upon theconcrete or similarfloor structure to provide top surface whichis actually composed of theheat exchanger heat radiating surface. The tubes of the heat exchangerare secured to the backing plate by deformation of the plate to providegrooves within whichthe tubes are bottomed, with the plate beingdeformed about the tubes into greater than semi-peripheral contacttherewith to insure effective heat transfer from the tube to the plateand also to provide a substantially levelupper plate surface. changersare provided in standardized, prefabricated form so that they may beeasily installed by merely coupling a plurality of standardized unitstogether.

It will thus be seen that the present invention constitutes animprovement 'over the prior art radiant floor heating panel in that theuse of standardized, pie-fabricated units provides a flexible, easilyinstalled, readily erected heating system. "The heat exchangers areinstalled on the surface of the sub-floor structure so that useful heatoutput is increased, 'heat losses to the ground are decreased, and the'time la'g re- The heat exsponse to temperature demand is improved andthe heat exchangers simultaneously provide not only the heating systembut also a level ba'se surface for a superimposed floor covering.

It is, therefore, an important object of the present invention toprovide a radiant floor heating panel composed of a plurality ofstandardized plate and tube-type units carried by a floor'basestructure.

Another important object of the present invention is to provide aradiant fioor heating panel including a sub-floor structure and a plateand tube-type heat exchanger superimposed on the floor structure, withthe heat exchanger backing plate forming an upper floor surface.

A further important object of the present invention is to provide afloor heating panel including a solidified fioor base structure and atube and plate-type heat exchanger superimposed on said base structureand partially embedded therein with the heat exchanger backing plateforming a level floor surface overlying the base structure.

Yet another important object of the present invention is to provide aradiant floor heating panel comprising a concrete floor base, a groovedheat exchanger backing plate superimposed on said base to form a levelupper surface therefor with the plate grooves being embedded in saidbase structure, and a sinuous heat exchanger tube bottomed in thegrooves for circulating a heat exchange fluid in effective heat exchangerelation with the plate.

Other and further important objects of this invention will be apparentfrom the disclosures in the specification and the accompanying drawings.

On the drawings:

Figure 1 is a plan view, partly in section, illustrating a radiant floorheating panel of the present invention;

Figure 2 is a greatly enlarged view similar to Figure 1; and

Figure 3 is a greatly enlarged sectional view taken along the planeIII-III of Figure 1.

As shown on the drawings:

In Figure 1, the reference numeral it! refers to a building, such as adwelling or the like, having upstanding side walls ll formed of suitablematerial, such as poured concrete or thelike. The building I!) isprovided witha concrete floor slab (Figure 3) preferably poured in twocourses, including a base course I2 and a superimposed fine course IS.The base course may desirably be about fourinches thick and formed ofordithree inches thick and is cast directly upon the base course, and itwill be appreciated that other light-weight aggregates, such as Perliteor the like, may also be utilized in the finish course.

The finish course is preferably laid out in panels which are defined bywooden screed boards [4 which are set on end and retained in uprightposition by the subsequently solidified finish course l3. It will benoted that the upper level of the finish course l3 corresponds in heightto the height of the screed boards It, so that a substantially constantlevel sub-fioor surface is provided.

The radiant heating panel of the present invention is defined by aplurality of tube and plate-type heat exchangers which are positionedupon and extend transversely between the screed boards 14. Moreparticularly, it will be seen in Figure 1 that a plurality oflongitudinally extending screed boards l4 are provided for transversealignment, the screed boards being longitudinally aligned in pairs so asto leave a central transverse space therebetween. This space is definedby form boards it which contact corresponding ends of each set of screedboards, so that the foundation of the building I l is divided in twolongitudinally spaced sets of panels divided by the space [5 whichdefines a pipe chase.

Plate and tube-type exchangers are positioned within each panel definedby the sets of screed boards and the associated form boards IS. Theheat'exchangers H are best illustrated in Figures 2 and 3 and consist ofa backing plate l8 having grooves l9 formed therein to extend inparallel spaced relation across the width of each plate. The plate [8 isdeformed, as at 20, in the upper portions of each of the grooves It tooverlie an intermediate diameter of a tube 2i associated with the plateand bottomed in the grooves IS. The tube 2| has straight portions lyingwithin the grooves l9 and curved joining portions 2m projecting beyondthe plate to joint adjacent straight portions, thereby defining acontinuous sinuous tube length. It will thus be seen that the deformedportions 2b of the plate [9 overlie the tubes so as to securely clampthe tubes to the plate in intimate, elongated surface contact and ineffective heat transfer relation. The groove deformed portions defineundercuts 2| which extend along the entire length of each straight tubelength, while the upper surface of the plate 18 is substantially plainwith the exception of the space between the plate deformed portions 20directly overlying the tube.

Informing the radiant heating panel of the present invention, the plateE8 of each exchanger I7 is positioned to overlie the sub-floor structurewith its lateral margins bearing upon adjacent screed boards M tosupport the plate along the length. It will be seen that the grooves l9and tubes 2| carried thereby project downwardly into upper course I3 ofthe sub-floor and the heat exchangers are so positioned while the uppercourse is still fluid, or at least capable of flowing. Following thepositioning of the heat exchanger IT, as hereinbefore described, theheat exchangers are lightly tamped and pressed to form a level surfacewith the plate grooves and tubes becoming embedded within the upperregions of the upper course [3. The fluid material of the upper coursewill enter the undercut area 22 so that, when the whole assembly ispermitted to stand until the concrete is hard, the heat exchanger willbefirmly bonded in the position illustrated in Figure 3.

To complete the assembly of the radiant heating panel, adjacent heatexchange panels are joined by suitable piping as particularlyillustrated in Figure 2, wherein it will be seen that the straightterminal ends 2lb of adjacent heat exchangers I1 are joined by means ofelbows 24 and transverse joining piping 25. The straight ends 2lb of thetubes 2| project outwardly to overlie the form boards [6, oralternatively, the form boards It may be recessed to accommodate thetubing ends. Inasmuch as a complete panel is provided on each side ofthe pipe chase IS, a header pipe 26 connected to a source of heatedfluid, such as a steam boiler, or the like, is connected to lead piping25a for each panel through suitable plumbing which need not be describedin detail. A return line 21 to the source of heated fluid is connectedwith the outlet ends 28 of the heat exchangers in each' panel, so thatre-, turn flow of heat exchange fluid to the primary heat exchanger maybe accomplished. Preferably, the point where the terminal ends 28 jointhe return line 2'! is the low point of the installation, so that atleast some measure of gravity flow of heat exchange fluid is obtained.

It will be seen that the present invention thus provides an improvedradiant fioor heating panel having the advantages hereinbefore setforth. First, the heating panel is composed of standardized,pre-fabricated elements which are capable of fiexible utilization andcheap installation. Secondly, the heat exchangers are installed upon thesurface of the sub-floor or concrete slab rather than being completelyembedded in or buried under the slab so as to increase the useful heatoutput, to decrease reverse heat losses to the ground, and to reduce thetime lag response to temperature demands of the building. Thirdly, theheat exchanger not only provides a heat exchange surface overlying thesub-floor. but also actually provides the finished sub-floor surface towhich suitable floor covering, such as linoleum, asphalt tile, or thelike, may be directly applied. In addition, the heat exchanger plate Itprovides an extended radiation surface which underlies the completefloor covering area, giving an even heat without temperature variationto any material extent across the complete'dimensions of the panel. Theresulting even temperatures, which may be obtained, the improved heatoutput, and quick response to heating demands will be readilyappreciated by those skilled in the art. 7 7

It will be understood that modifications and. variations may be effectedwithout departing from the scope of the novel concepts of the presentinvention. a

I claim as my invention:

A radiant floor heating structure comprising a two-course concrete floorslab including a base course of coarse aggregate and a finish course ofa light-weight aggregate concrete, a plurality of rectilinearly arrangedpartition members defining generally rectangular fioor sections embeddedin said top course, plate and tube type heat exchangers each including abacking plate having plane edge portions in contact with and supportedby said partition members and extending in flush surface relationshipwith the adjacent heat exchangers to provide a level upper surface forsaid floor structure, said backing plates having spaced, parallelgrooves formed therein, and heat exchanger tubing seated in said groovesand adapted for the flow of heat exchange fluid therethrough, the Wallsdefining said plate grooves overlying the tubing disposed therein toengage more than a semi-periphery of said tubing and to providere-entrant groove portions on the under surface of said plate into whichthe material of said upper course extends to anchor said heat exchangersthereto.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,746,231 Barker Feb. 11, 1930 1,800,150 Musgrave et a1 Apr.7, 1931 10 2,281,299 Steenstrup Apr. 28, 1942 FOREIGN PATENTS NumberCountry Date 274,664 Great Britain July 28, 1927 321,450 Great BritainNov. 11, 1929

